1. Field of the Invention
This invention relates to dental retainers or appliances for straightening and retaining teeth and more particularly, to a phosphorescent or glow-in-the-dark plastic dental appliance and method of construction, which appliance is particularly suitable for children. Using a vacuum or pressure thermoforming machine and a sheet, plate or disc of thermoformable plastic which is typically impregnated or coated with a phosphorescent material, the glow-in-the-dark appliance is vacuum-thermoformed over the dental impression cast and allowed to set on the cast. After removal from the cast, the appliance is capable of glowing in the dark for a limited period of time after exposure to a light source and as the appliance is worn on the patient""s dentition. The appliance is capable of repeated phosphorescence throughout the dental treatment period.
2. Description of the Prior Art
A xe2x80x9cThermoformed Plastic Dental Retainer and Method of Constructionxe2x80x9d is described in my U.S. Pat. No. 5,692,894, dated Dec. 2, 1997. The dental retainer is constructed by first forming an impression of a patient""s upper or lower dentition and constructing a cast from the impression. The retainer is vacuum thermoformed over the cast using a sheet, plate or disc of thermoformable plastic and a vacuum or pressure thermoforming machine. A protrusion or divot is formed in the retainer on the labial or lingual side of each tooth which is to be repositioned lingually or labially, respectively, and a gap, opening or window is formed in the retainer on the opposite side of the divot to accommodate unhindered tooth repositioning movement. As the retainer is worn on the patient""s dentition over a period of days or weeks, the projecting divots apply pressure to the respective teeth and push the teeth into the gap or window of the retainer to a straightened position. By appropriately positioning the divots in the retainer with respect to the patient""s malpositioned teeth, the teeth can be moved labially, lingually or rotated, as needed, for straightening.
My application Ser. No. 09/568,727 describes a xe2x80x9cThermoformed Plastic Dental Retainer and Method of Constructionxe2x80x9d. The dental retainer is constructed by first forming an impression of a patient""s upper or lower dentition and constructing a cast from the impression. The retainer is vacuum-thermoformed over the cast using a sheet, plate or disc of thermoformable plastic and a vacuum or pressure thermoforming machine. As the thermoformed plastic retainer sets on the cast, the retainer is rapidly cooled typically by spraying a refrigerant coolant on the retainer. This step causes the retainer to thermally contract against and precisely conform to the configuration and texture of the cast for an accurate and tight fit of the retainer on the patient""s dentition.
U.S. Pat. No. 6,095,146, dated Aug. 1, 2000, to Knauer, et al., discloses xe2x80x9cGlow-In-The-Dark Hearing Protective Devicesxe2x80x9d, each including a semi-aural device, an earplug or an earmuff. A glow-in-the-dark material is incorporated into at least a part of the device such that the device emits light for an extended period of time in the dark after exposure to light. The glow-in-the-dark material can be disposed on a surface of the device or dispersed throughout the material which forms the device.
It is an object of the present invention to provide a glow-in-the-dark dental appliance and method of constructing the appliance.
Another object of the invention is to provide a glow-in-the-dark, thermoformed plastic dental appliance which is particularly suitable for children.
Still another object of the invention is to provide a thermoformed phosphorescent dental appliance and method of construction of the appliance including typically vacuum-thermoforming a sheet, plate or disc of phosphorescent plastic on a dental impression cast constructed from an impression of a typically pediatric patient""s upper or lower dentition, and allowing the thermoformed appliance to set on the cast.
Yet another object of this invention is to provide a thermoformed plastic dental appliance and method of construction of the appliance, including initially forming an impression of a patient""s upper or lower dentition and constructing a cast from the impression; vacuum or pressure-thermoforming the appliance over the cast using a vacuum or pressure thermoforming machine and a sheet, plate or disc of thermoformable plastic which is typically impregnated or coated with a phosphorescent material; and allowing the thermoformed plastic appliance to set on the cast, whereby the appliance is capable of glowing in the dark for a limited period of time after exposure to a light source and as the appliance is worn on the patient""s dentition.
These and other objects of the invention are provided in a glow-in-the-dark thermoformed plastic dental appliance and method of construction. The dental appliance is constructed by first forming an impression of a typically pediatric patient""s upper or lower dentition and constructing a cast from the impression. The appliance is thermoformed over the cast using a vacuum or pressure thermoforming machine and a sheet, plate or disc of thermoformable plastic impregnated or coated with a phosphorescent material. After the thermoformed plastic appliance sets on the cast, the appliance is removed from the cast and is capable of glowing in the dark for a limited period of time after exposure to visible light and as the appliance is worn on the patient""s dentition, and is capable of repeated phosphorescence throughout the dental treatment period.